Electrical connection



Jan. 7 1936. 5 TEM. 2,026,755

ELECTRICAL CONNECTION Original Filed June 22, 1928 Ag ATTORNEY INVENTOR Patented Jan. 7, 1936 UNITED STATES ELECTRICAL CONNECTION 7 Edgar S. Stem, Alderson, Pa., assignor of one-half to Albert A. Stull, Alderson, Pa.

Application June 22, 1928, Serial No.'287,606

Renewed May 10, 1935 Claims. (Cl. 173-343) This invention relates to electrical connections and moreparticularlyto electrical connections including a part having contact tangs extending therefrom in the same direction and a tang-re- 6 ceiving part having contact springs to be engaged by said tangs when inserted into the'secon'd part.

The tang-bearing and tang-receiving parts of such connections are frequently pulled apart in use, thus causing inconvenience and annoyance.

10 An important object of the invention is to provide devices of the kind specified which will be substantially free from suchdifilculties and at the same time be so constructed and arranged as to be separated easily when it is desired to do so.

Another object of the invention is to provide connecting devices including a member having tangs extending in the same direction therefrom, at least one of said tangs having a rearwardly facing shoulder, and a tang-receiving member having a catch adapted to engage said shoulder upon insertion of the tangs and. cooperate with said shoulder to prevent accidental withdrawal of the tangs, the construction and arrangement being such that by a slight relative movement, as,

for example, rotation of the two members, in a direction transverse to the tang, the locking engagement between the tang and the catch or locking device will be broken, thus enabling ready separation of the tang-carrying and tang-receiving members.

Although for illustrative purposes, an arrangement in the form of a plug with a tang-receiving portion adapted to be screwed into a screw-socket and a tank-carrying portion adapted for use with the tang-receiving portion, is shown and described; it should be understood that the tangreceiving portion of the connection may be of other forms, for example, an electrical outlet in a wall or the like.

A further feature of the invention resides inthe provision of tang-locking and controlling devices which may be used with ordinary tangs which would not cooperate therewith for locking purposes, as well as with tangs adapted to cooperate 5 with such locking devices.

It should also be understood that the locking or latching devices may be associated with the contact springs of the tang-receiving parts of the electrical connections and may be integral therewith or separate therefrom.

Other features and advantages will appear upon consideration of the following description and the drawing, in which: 7

Fig. 1 is a view in elevation of a connection illustrating a satisfactory embodiment of the pres-- ent invention, part of the structure being broken away to show the locking device at the farther side;

Fig. 2 is a view of a connection in which the tang-carrying part is shown in central section and gives a view of the locking devices in a direction at right angles to the line of view in Fig. 1;

Fig. 3 is a sectional plan view taken along the line 3--3 of Fig. 1;

Fig. 4 is a view illustrating a combined contact spring and locking device in which the parts are integral with each other; and Fig. 5 is a view similar to Fig. 3 but with the locking and controlling device proper separate from the contact spring. 7 10 Referring to the drawing, I0 designates an electrical connection or plug includinga part 'or cap It from which tangs or contacts I2 project in the same direction, and a tang-receiving part or base I3 including contact members in the form of 15 leaf springs I4 and I5 and having their outer ends turned out of alignment sufficiently to assureengagement thereof by said tangs I2 for pushing the leaf springs to one side and maintaining effective contact therewith. Preferably the body of the go 7 cap II is of insulating material and the tangs which are substantially parallel are connected therewith at one end and also to conductors in a cord Ita which extends centrally through the cap at its outer side. The tangs i2 are substantially the same as those in general use but each of them is provided with a recess or notch I6 fora purpose to be brought out more clearly hereinafter.

The base I3 consists of a body of insulating material having openings I1 and I8 therethrough 30 to receive respectively the leaf springs or contacts i4 and I5. The leaf spring I4 is connected at the lower end of the base with a screw-threaded shell I9 surrounding the base and adapted to be screwed into a suitable socket. The end of the 35 base I3 adjacent the screw-threaded shell l9is covered by a plate 20 of insulating material having at its center a perforation to receive a metallic member 2I secured in the base I3 and extending axially therefrom. The contact or leaf spring 40 so as to press the spring member 24 against the 60:

offset 22 of the contact I5, the offset 22 in turn engaging the outer face of the insulating member'20 and holding it against the body of the base I3.

The structure thus far described is in general 553 the same as for plugs heretofore in use. In the illustrative embodiment of the invention, tanglocking devices are provided in connection with each of said spring contacts I4 and I5. These locking devices may be substantially the same for 00 both contacts and it will therefore be suflicient to describe the locking device associated with the contact spring l5.

One form of combined contact spring l5 with the locking device or devices is shown in Fig. 4. The actual locking is done by' means of a leaf spring extending upwardly from the offset or base 22 of the contact and having its upper end directed inwardly to form a hook 26 adapted to enter the notch l6 of a tang 12 when 'thecap II and base l3 are pressed together. In this connection it should be noted that the upper surface of the hook curves downwardly so that when engaged by the rounded lower edge of a tang l2 it may be forced back and held in such condition until a recess or notch I6 is brought into position to permit the hook 26 to enter the same.

In order to assure proper positioningof the hook 26 for engagement by a tang during insertion, a portion of the spring contact 15 adjacent to the spring 25 may be utilized to limit the forward movement of the spring 25 and hook 26. As here shown, the stop portion of the spring contact I 5 is in the form of a lug orstop 21 at the edge of the contact and substantially perpendicular to the flat portion of the spring contact. To assure proper guiding of the tang I 2 to be brought into engagement with the spring contact l5 the offset or base 22 is provided'at its edge opposite the spring 25 with another'leaf" spring 28 directed outwardly at its upper end so as-to facilitate the insertion of the end of the tang. This leaf spring 28 not only assures proper cooperation of an inserted tang with the hook 26 but also permits movement of the tang away from the hook 215, by relative rotation ofthe tang bearing member and the tang receiving member about an axis substantially parallel to thetangs to effect unlocking of the tang and the hook so that the cap II and the base l3 may be separated.

As shown in Fig. 4 the springs or looking members 25 and 28 are integral with the spring l5. In

come cases, however, it may be desirable to have the springs 25 and 28, constituting the principal parts of the locking device, separate from the spring I5. As shown in Fig.5, this're'sult is obtained by forming the springs 25 and 28 of 'a single piece including a connecting portion 29 to be placed beneath the oifset'22 of the spring I5;

In this arrangement of the spring 15 and locking members 25 and 2B, the forward movement of the member 25 may be limited, as in Fig. 4, by 3, lug 21 projecting from one edge of the contact spring I 5'.

The proper relative positions 'of the contact and locking and controlling device shown in Fig. 5, may be maintained in any suitable manner.

It will be evident that; although the locking devices are designed to cooperate with suitable tangs, the base [3 is fully adapted for use with tangs which have no special'formation' to cooperate with the locking devices. 7

It should be understood that various changes may be made in the construction and arrangement of the parts and that certain parts may be used without others, without departing from the true spirit and scope of the invention.

Having thus described my invention, I claim:

1'. An electrical connection device adapted to receive parallel contact tangs on another connection device, including contact springs tobe engaged by said tangs, and means for interlocking said connection devices, including a separate spring latch adjacent and movable with respect to one of the contact springs in thetangreceiving device, and adapted to engage a recess in a tang when thrust into engagement with such spring, the arrangement being such that the interlocking means will be released upon a slight relative rotation of said contact devices about an axis parallel to and midway between said tangs.

2. A device'for use in an electrical connection part adapted. to receive contact tangs projecting in the same direction'from another part, including a leaf spring contact shaped at one end to be engaged by the forward end of a tang and pressed to one side as the tang is moved therealong, a latching device including a leaf spring arranged to act across the face of said leaf spring contact and having a projection adapted to engage a rearwardly facing shoulder at the edge of a tang inserted along said leaf spring contact, and a leaf spring adjacent to the opposite edge of said leaf spring contactadapted to press a tang toward'the leaf spring of the latching device so that when the tang reaches the proper position, saidadjacent leaf spring will enable the projection to engage over said shoulder, and yield to enable lateral separation of said latch and shoulderin a direction across said leaf spring contact.

3. 'An electrical connection including a cap with contact tangs projecting therefrom in the same direction and each having'a rearwardly facing shoulder at one edge thereof, a tang-receiving part having main parallel leaf spring contacts to be engaged by-said tangs, and means normally effective for'preventing separation of said cap and tang-receiving part including a latch in the form of a leaf spring adjacent to one edge of one of said contact springs and shaped to enable a tang to'be inserted along the adjacent spring contact and then to engage the shoulder on the tang, and a guiding spring to direct such tang intoproper position along the contact but-permitting lateral movement of the tang to release it from-the latch.

4. In an electrical connection, a leaf spring conhaving a hooked upper end serving as a latch to engage a shoulder at the edge of said tang, a stop on said contact to limit the forward movement of the latch spring, and a leaf spring at the other edge of the contact spring with an outwardlydirected upper end and acting to guide the tang into operative engagement with said latch while permitting lateral movement of the tang to release it from-thelatch.

5. In an electrical connection, a leaf spring contact arranged for engagement by a contact tang, a leafspring at one edge of said contact and having a hooked upper end serving as a latch to engagea shoulder at'the edge of said tang, a stop on said contact to limitthe forward movement of the latchspring, and a leaf spring at the other edge-of the contact spring withan outwardly directed upper end and acting to guide the tang intooperati've engagement with said latch while permitting lateral movement of the tang to release it from the latch, thelatch spring and the guiding spring being integral at their inner ends.

EDGAR S. STEM. 

